This invention relates to beard and mustache trimmers and, more particularly, to control systems for moving a comb element relative to the cutting blade.
During the last many years, individuals have been increasingly drawn to the advantages provided by electric shaver""s and electric hair trimmers. In general, the consuming public has found that the use of scissors, razors, and other cutting systems are extremely inconvenient for removing, trimming, or maintaining beards, mustaches, and hair lengths. In particular, cutting or trimming children""s hair is often difficult with prior art methods. In addition, with the ever-increasing time constraints and commitments individuals typically encounter, a fast and effective trimming or cutting system is most desirable.
Through the years, numerous alternate constructions have been created for hair trimmers, particularly suited for beards and mustaches and hair. Most of these prior art systems employ similar cutting systems in combination with a movable comb element which is positioned in overlying, co-operating relationship with the cutting blades. Typically, one fixed blade and one movable blade cooperate to perform the hair or whisker cutting function, while the comb element establishes a fixed length from the skin surface at which the hair fibers will be cut.
In order to provide a hair trimmer which is capable of being used in a wide variety of alternate hair cutting situations, the comb element associated with the hair trimmer is movably adjustable relative to the cutting blades, in order to allow the user to control the length at which the hair fibers are cut. Unfortunately, prior art constructions have been incapable of providing an adjustable comb element which is easy to employ, while also assuring secure locked engagement of the comb element in any desired position.
Typically, in these prior art constructions, the comb element is either extremely difficult to move or to adjust between its alternate positions. Alternatively, in those prior art systems where movement of the comb element is capable of being achieved with reasonable ease or convenience, the comb element is not securely retained in any desired position. Instead, the comb element easily returns to its original position, whenever any pressure is applied to the comb element.
This unwanted movement of the comb element is extremely difficult for the user to endure, since the user is attempting to cut the beard, mustache, or hair fibers to a specific length. In this regard, whenever the position of the comb element moves during use, the hair fibers are cut to a substantially different length and the desired uniformity or consistency is lost.
By employing the present invention, all of the difficulties and drawbacks found in prior art hair trimmers are completely eliminated and a secure, easily employed, dependable, and reliable movable comb control system is achieved. In accordance with the present invention, a user controlled advancing system is provided which is constructed for controllably moving an elongated arm a preset distance each time this system is activated.
In the present invention, a rotatable wheel is mounted in cooperating engagement with a longitudinally movable arm or slide member. However, contrary to prior art constructions which employ a rack and pinion control system, the present invention incorporates cam slots formed in the wheel with the slots positioned for controlled engagement with cam pins formed on the movable arm or slider. By employing this construction, rotational movement of the wheel causes controlled movement of the cam pins which results in the desired longitudinal movement of the arm/slider. By securing the elongated arm/slider to the comb element, either directly or through an interconnecting plate, the longitudinal movement of the arm/slider causes the comb element to move simultaneously therewith.
By constructing the cam slots of the wheel member in a generally radial, arcuately curved pattern having a serpentine surface or wall, a plurality of separate and independent stop positions are established. In addition, the arm member is mounted in controlled cooperating relationship with the wheel member, sandwiched between an upper and lower housing.
As a result of this construction, the arm/slider is capable of longitudinal movement in a single plane, with the longitudinal movement being completely controlled by the sliding engagement of the cam pins of the arm/slider in the cam slot of the rotatable wheel. In this way, the desired easily employed, secure and dependable movement of the comb element attached to the arm member is achieved by simply rotating the wheel in a desired direction, causing the cam pins of the arm member to move between the stop positions formed along the cam slot of the wheel.
In the preferred construction of the present invention, the rotatable wheel member incorporates two separate and independent cam slots formed therein, with each cam slot being formed on opposed side surfaces of the wheel member. In addition, two separate and independent cam pins are formed on the arm member, with each cam pin being positioned for cooperating with one cam slot.
Furthermore, the entry zones or portals for each cam slot of the wheel member are formed at diametrically opposed positions. As a result, by properly positioning the cam pins on the arm/slider, the rotational movement of the wheel controls one cam pin at a time, with the first pin exiting one cam slot while the second pin enters the second cam slot. In this way, the total longitudinal travel distance of the arm/slider is maximized for the diameter of the wheel.
In addition to providing a plurality of positions for the movement of the arm/slider by the rotation of the wheel, the construction of the cam slots with its serpentine surface or wall also provides an inherent abutment stop for each position, preventing unwanted, sliding movement of the arm member relative to the cam slot independently of the user initiated rotation of the wheel. As a result, axial or longitudinal movement of the arm is incapable of occurring accidentally and the desired secure engagement of the comb element in each position is realized.
By rotationally moving the wheel member in a desired direction, the comb member is quickly and easily advanced into any desired position, while also assuring that the comb member is securely retained in any selected position. Furthermore, as detailed above, once the comb member has been placed in a desired position, axial movement of the comb member due to conventional pressure being applied thereto is eliminated by the present invention. In this way, all of the goals and objects desired by the present invention are attained.
A further feature preferably incorporated into the comb control system of the present invention is the incorporation of positive-position stops or indicators. In the preferred construction, the wheel member incorporates a plurality of grooves formed in an outer wall portion thereof in substantially equal spaced intervals. In addition, a spring arm is mounted for biased engagement in each groove as the wheel is rotated.
By employing this construction, the rotation of the wheel member causes the spring member to move from one groove to the next providing a positive, audible click, while also providing a resistance to rotational movement which must be overcome to move the wheel and arm/slider into the next position. In addition, the wheel member also preferably incorporates a visual indicator such as a number, to further assist the user in recognizing each position.
The invention accordingly comprises the features of construction, combination of elements and arrangement of parts which will be exemplified in the construction hereinafter set forth, and the scope of the invention will be indicated in the claims.